[New Feature] Infinfite scroll for wheel plugin

[dpa99c]

What problem does this feature solve?

The wheel plugin is great for implementing iOS-style pickers.

However, similar to native iOS date/time picker UI, it would be useful to be able to have an option to infinitely scroll the wheel so once the last value in the list is reached, the first value appears again, giving the impression it really is a circular wheel.

In my use case, I am creating a combination lock using the wheel plugin so it makes sense that the rotation would be infinite, like a real physical combination lock, for example:

While it's possible to implement a pseudo-infinite wheel by repeating the given values a large number of times as suggested here, this can both potentially affect performance due to the large number of DOM nodes and also as pointed out in the comments, a diligent user may still scroll to the end.

What does the proposed API look like?

I imagine this would just require a boolean infinite flag in the wheel options, e.g.:

const bs = new BScroll('.wrapper', {
  wheel: {
    wheelWrapperClass: 'wheel-scroll',
    wheelItemClass: 'wheel-item',
    rotate: 25,
    adjustTime: 400,
    selectedIndex: 0,
    wheelDisabledItemClass: 'wheel-disabled-item',
    infinite: true
  }
})